Source code for rxgrep.cs

```
using System;
```
```
using System.Collections.Generic;
```
```
using System.IO;
```
```
using System.Linq;
```
```
using System.Text.RegularExpressions;
```
```
 
```
```
 
```
```
namespace RobvanderWoude
```
```
{
```
```
	class RxGrep
```
```
	{
```

		static readonly string progver = "3.02";

```
 
```
```
 
```
```
		#region Global Variables
```
```
 
```
```
		static bool dedup = false;
```
```
		static bool returngroup = false;
```
```
		static bool singlelinemode = false;
```
```
		static int skipmatches = 0;
```
```
		static int takematches = 0;
```
```
		static string groupseparator = " ";
```

		static List<int> groupnums = new List<int>( );

```
		static int bytes = -1;
```

		static List<string> dedupedmatches = new List<string>( );

```
 
```
```
		#endregion Global Variables
```
```
 
```
```
 
```
```
		static int Main( string[] args )
```
```
		{
```
```
			#region Initialize Variables
```
```
 
```
```
			bool caseset = false;
```
```
			bool quiet = false;
```
```
			bool skipset = false;
```
```
			bool takeset = false;
```
```
			string filename = string.Empty;
```
```
			string pattern;
```
```
			string input = string.Empty;
```
```
			int matchcount;
```

			int redirectnum = ( Console.IsInputRedirected ? 1 : 0 );

			RegexOptions regexoptions = RegexOptions.None;

```
 
```
```
			#endregion Initialize Variables
```
```
 
```
```
 
```
```
			#region Command Line Parsing
```
```
 
```
```
			if ( args.Length + redirectnum < 2 )
```
```
			{
```
```
				return ShowHelp( );
```
```
			}
```
```
 
```

			List<string> arguments = new List<string>( args );

```
			if ( arguments.Contains( "/?" ) )
```
```
			{
```
```
				return ShowHelp( );
```
```
			}
```
```
 
```
```
			if ( !Console.IsInputRedirected )
```
```
			{
```
```
				filename = arguments[0];
```
```
				arguments.RemoveAt( 0 );
```
```
			}
```
```
			pattern = arguments[0];
```
```
			arguments.RemoveAt( 0 );
```
```
 
```

			foreach ( string option in arguments )

```
			{
```

				switch ( option.ToUpper( ).Substring( 0, 2 ) )

```
				{
```
```
					case "/?":
```
```
						return ShowHelp( );
```
```
					case "/A":
```
```
						if ( groupseparator == "\t" )
```
```
						{
```

							return ShowHelp( "Duplicate switch /A" );

```
						}
```
```
						groupseparator = "\t";
```
```
						break;
```
```
					case "/D":
```
```
						if ( dedup )
```
```
						{
```

							return ShowHelp( "Duplicate switch /D" );

```
						}
```
```
						dedup = true;
```
```
						break;
```
```
					case "/F":
```
```
						if ( bytes != -1 )
```
```
						{
```

							return ShowHelp( "Duplicate switch /F" );

```
						}
```
```
						try
```
```
						{
```

							bytes = Convert.ToInt32( option.Substring( 3 ) );

```
						}
```
```
						catch ( Exception e )
```
```
						{
```

							Console.Error.WriteLine( "Error: {0}", e.Message );

							return ShowHelp( string.Format( "Invalid command line switch \"{0}\"", option ) );

```
						}
```
```
						break;
```
```
					case "/G":
```
```
						returngroup = true;
```
```
						int groupnum = 0;
```
```
						try
```
```
						{
```

							groupnum = Convert.ToInt32( option.Substring( 3 ) );

```
							if ( groupnum < 1 )
```
```
							{
```

								return ShowHelp( "Invalid group number {0} specified", groupnum.ToString( ) );

```
							}
```
```
						}
```
```
						catch ( Exception e )
```
```
						{
```

							Console.Error.WriteLine( "Error: {0}", e.Message );

							return ShowHelp( string.Format( "Invalid command line switch \"{0}\"", option ) );

```
						}
```
```
						if ( groupnum > 0 )
```
```
						{
```
```
							groupnums.Add( groupnum );
```
```
						}
```
```
						break;
```
```
					case "/I":
```
```
						if ( caseset )
```
```
						{
```

							return ShowHelp( "Duplicate switch /L" );

```
						}
```

						regexoptions |= RegexOptions.IgnoreCase;

```
						caseset = true;
```
```
						break;
```
```
					case "/L":
```
```
						if ( singlelinemode )
```
```
						{
```

							return ShowHelp( "Duplicate switch /I" );

```
						}
```
```
						singlelinemode = true;
```
```
						break;
```
```
					case "/Q":
```
```
						if ( quiet )
```
```
						{
```

							return ShowHelp( "Duplicate switch /Q" );

```
						}
```
```
						quiet = true;
```
```
						break;
```
```
					case "/S":
```
```
						if ( skipset )
```
```
						{
```

							return ShowHelp( "Duplicate switch /S" );

```
						}
```
```
						try
```
```
						{
```

							skipmatches = Convert.ToInt32( option.Substring( 3 ) );

```
						}
```
```
						catch ( Exception e )
```
```
						{
```

							Console.Error.WriteLine( "Error: {0}", e.Message );

							return ShowHelp( string.Format( "Invalid command line switch \"{0}\"", option ) );

```
						}
```
```
						break;
```
```
					case "/T":
```
```
						if ( takeset )
```
```
						{
```

							return ShowHelp( "Duplicate switch /T" );

```
						}
```
```
						try
```
```
						{
```

							takematches = Convert.ToInt32( option.Substring( 3 ) );

```
						}
```
```
						catch ( Exception e )
```
```
						{
```

							Console.Error.WriteLine( "Error: {0}", e.Message );

							return ShowHelp( string.Format( "Invalid command line switch \"{0}\"", option ) );

```
						}
```
```
						break;
```
```
					default:
```

						return ShowHelp( string.Format( "Invalid command line {0}: \"{1}\"", ( option[0] == '/' ? "switch" : "argument" ), option ) );

```
				}
```
```
			}
```
```
 
```
```
			#endregion Command Line Parsing
```
```
 
```
```
 
```

			#region Command Line Arguments Validation

```
 
```
```
			if ( Console.IsInputRedirected )
```
```
			{
```

				// Read the redirected Standard Input

```
				input = Console.In.ReadToEnd( );
```
```
				if ( bytes != -1 )
```
```
				{
```

					input = input.Substring( 0, Math.Min( bytes, input.Length ) );

```
				}
```
```
			}
```
```
			else
```
```
			{
```
```
				// Check if the file name is valid
```
```
				if ( filename.IndexOf( "/" ) > -1 )
```
```
				{
```
```
					return ShowHelp( );
```
```
				}
```

				if ( filename.IndexOfAny( "?*".ToCharArray( ) ) > -1 )

```
				{
```

					return ShowHelp( "Wildcards not allowed" );

```
				}
```
```
				// Check if the file exists
```
```
				if ( File.Exists( filename ) )
```
```
				{
```
```
					// Read the file content
```

					using ( StreamReader file = new StreamReader( filename ) )

```
					{
```
```
						if ( bytes == -1 )
```
```
						{
```
```
							input = file.ReadToEnd( );
```
```
						}
```
```
						else
```
```
						{
```
```
							char[] buffer = new char[bytes];
```
```
							file.Read( buffer, 0, bytes );
```

							input = string.Join( string.Empty, buffer );

```
						}
```
```
					}
```
```
				}
```
```
				else
```
```
				{
```

					return ShowHelp( string.Format( "File not found: \"{0}\"", filename ) );

```
				}
```
```
			}
```
```
 
```

			if ( dedup && ( skipset || takeset ) )

```
			{
```

				return ShowHelp( "Switch /D cannot be combined with switches /S or /T" );

```
			}
```
```
 
```

			#endregion Command Line Arguments Validation

```
 
```
```
 
```

			// Now that the command line parsing is finally done, let's get some action

```
			if ( singlelinemode )
```
```
			{
```
```
				matchcount = 0;
```

				foreach ( string line in input.Split( new char[] { '\n', '\r' }, StringSplitOptions.RemoveEmptyEntries ) )

```
				{
```

					matchcount += DisplayMatches( line, pattern, regexoptions );

```
				}
```
```
            }
```
```
			else
```
```
			{
```

				matchcount = DisplayMatches( input, pattern, regexoptions );

```
			}
```
```
			return matchcount;
```
```
		}
```
```
 
```
```
 
```

		// The main functionality: display all matching substrings

		public static int DisplayMatches( string haystack, string needle, RegexOptions options )

```
		{
```
```
			int counter = 0;
```
```
			int displayed = 0;
```
```
			// Get all matches
```

			MatchCollection matches = Regex.Matches( haystack, needle, options );

```
			if ( dedup )
```
```
			{
```

				//List<string> dedupedmatches = new List<string>( );

```
				foreach ( Match match in matches )
```
```
				{
```
```
					if ( returngroup )
```
```
					{
```

						if ( match.Groups.Count >= groupnums.Count )

```
						{
```
```
							bool empty = true;
```

							foreach ( int groupnum in groupnums )

```
							{
```

								Group group = match.Groups[groupnum];

								if ( !dedupedmatches.Contains( group.Value ) )

```
								{
```
```
									if ( empty )
```
```
									{
```
```
										Console.Write( group.Value );
```
```
									}
```
```
									else
```
```
									{
```

										Console.Write( groupseparator + group.Value );

```
									}
```

									dedupedmatches.Add( group.Value );

```
									displayed += 1;
```
```
									empty = false;
```
```
								}
```
```
							}
```
```
							Console.WriteLine( );
```
```
						}
```
```
					}
```

					else if ( !dedupedmatches.Contains( match.Value ) )

```
					{
```
```
						Console.WriteLine( match.Value );
```

						dedupedmatches.Add( match.Value );

```
						displayed += 1;
```
```
					}
```
```
				}
```
```
			}
```
```
			else
```
```
			{
```
```
				if ( matches.Count > skipmatches )
```
```
				{
```
```
					foreach ( Match match in matches )
```
```
					{
```

						if ( counter >= skipmatches && ( displayed < takematches || takematches == 0 ) )

```
						{
```

							if ( returngroup && match.Groups.Count >= groupnums.Count )

```
							{
```
```
								bool empty = true;
```

								foreach ( int groupnum in groupnums )

```
								{
```

									Group group = match.Groups[groupnum];

```
									if ( empty )
```
```
									{
```
```
										Console.Write( group.Value );
```
```
									}
```
```
									else
```
```
									{
```

										Console.Write( groupseparator + group.Value );

```
									}
```
```
									displayed += 1;
```
```
									empty = false;
```
```
								}
```
```
								Console.WriteLine( );
```
```
							}
```
```
							else
```
```
							{
```

								Console.WriteLine( match.Value );

```
								displayed += 1;
```
```
							}
```
```
						}
```
```
						counter += 1;
```
```
					}
```
```
				}
```
```
			}
```
```
			return displayed;
```
```
		}
```
```
 
```
```
 
```
```
		#region Error Handling
```
```
 
```

		public static int ShowHelp( params string[] errmsg )

```
		{
```
```
			#region Error Message
```
```
 
```
```
			if ( errmsg.Length > 0 )
```
```
 
```
```
			{
```

				List<string> errargs = new List<string>( errmsg );

```
				errargs.RemoveAt( 0 );
```
```
				Console.Error.WriteLine( );
```

				Console.ForegroundColor = ConsoleColor.Red;

```
				Console.Error.Write( "ERROR:\t" );
```

				Console.ForegroundColor = ConsoleColor.White;

				Console.Error.WriteLine( errmsg[0], errargs.ToArray( ) );

```
				Console.ResetColor( );
```
```
			}
```
```
 
```
```
			#endregion Error Message
```
```
 
```
```
 
```
```
			#region Help Text
```
```
 
```
```
			/*
```
```
			RxGrep,  Version 3.00
```
```
			Multi-line FindStr/Grep like tool
```
```
 
```

			Usage:   RXGREP  filename  pattern  [ options ]

			or:      command  |  RXGREP  pattern  [ options ]

```
 
```

			Where:   filename   is the file to be filtered

			         command    is the command whose standard output is to be filtered

			         pattern    is the search pattern (regular expression)

```
 
```

			Options: /A         use tAb as separator for multiple groups

```
			                    (default: space)
```

			         /D         do not show Duplicate matches

			         /F:nn      search only the First nn bytes

			         /G:nn      return match Group #nn (may be used multiple times)

			         /I         case Insensitive search

			         /L         single Line mode: ^ and $ match begin and end of each line

			         /Q         Quiet mode: no message if no match is found

			         /S:nn      Skip the first nn matches

			         /T:nn      Take only nn matches

```
 
```

			Example: ROBOCOPY D:\sourcedir E:\targetdir /NP /MIR |

			         RXGREP "\s+\d+\s+D:\\sourcedir\\[^\n\r]*\r\n([^\n\r\\]+\r\n)+"

			         (to be read as a single command line) will return something like:

			                         125    D:\sourcedir\subdir\

			            New File                 342        brandnewfile.ext

			            Newer                  4.06m        updatedfile.ext

			          *EXTRA File              2.40m        deletedfile.ext

```
 
```

			Notes:   If /F:nn is used and a file is specified, only the first nn bytes

			         of that file will be read; if the input is redirected, it is read

			         entirely, and then chopped to nn bytes before being searched.

			         /G:nn can be used multiple times; all matching groups are written

			         to screen, separated by spaces, unless /A is used, in which case

			         the matches will be separated by tabs; matching groups are shown

			         in order of input, not in order of command line arguments, e.g.

			         /G:1 /G:3 will show the same result as /G:3 /G:1.

			         Switches /D and /G cannot be combined with /S or /T.

			         Return code ("errorlevel") will equal the number of matches found,

			         or -1 in case of (command line) errors.

```
 
```
```
			Written by Rob van der Woude
```
```
			https://www.robvanderwoude.com
```
```
			 */
```
```
 
```
```
			#endregion Help Text
```
```
 
```
```
 
```
```
			#region Display Help Text
```
```
 
```
```
			Console.Error.WriteLine( );
```

			Console.Error.WriteLine( "RxGrep,  Version {0}", progver );

			Console.Error.WriteLine( "Multi-line FindStr/Grep like tool" );

```
			Console.Error.WriteLine( );
```
```
 
```
```
			Console.Error.Write( "Usage:   " );
```

			Console.ForegroundColor = ConsoleColor.White;

			Console.Error.WriteLine( "RXGREP  filename  pattern  [ options ]" );

```
			Console.ResetColor( );
```
```
 
```
```
			Console.Error.Write( "or:      " );
```

			Console.ForegroundColor = ConsoleColor.White;

			Console.Error.WriteLine( "command | RXGREP  pattern  [ options ]" );

```
			Console.ResetColor( );
```
```
 
```
```
			Console.Error.WriteLine( );
```
```
 
```
```
			Console.Error.Write( "Where:   " );
```

			Console.ForegroundColor = ConsoleColor.White;

```
			Console.Error.Write( "filename" );
```
```
			Console.ResetColor( );
```

			Console.Error.WriteLine( "   is the file to be filtered" );

```
 
```

			Console.ForegroundColor = ConsoleColor.White;

			Console.Error.Write( "         command" );

```
			Console.ResetColor( );
```

			Console.Error.WriteLine( "    is the command whose standard output is to be filtered" );

```
 
```

			Console.ForegroundColor = ConsoleColor.White;

			Console.Error.Write( "         pattern" );

```
			Console.ResetColor( );
```

			Console.Error.WriteLine( "    is the search pattern (regular expression)" );

```
 
```
```
			Console.Error.WriteLine( );
```
```
 
```
```
			Console.Error.Write( "Options: " );
```

			Console.ForegroundColor = ConsoleColor.White;

```
			Console.Error.Write( "/A" );
```
```
			Console.ResetColor( );
```

			Console.Error.Write( "         use t" );

			Console.ForegroundColor = ConsoleColor.White;

```
			Console.Error.Write( "A" );
```
```
			Console.ResetColor( );
```

			Console.Error.WriteLine( "b as separator for multiple groups" );

```
 
```

			Console.Error.WriteLine( "                    (default: space)" );

```
 
```

			Console.ForegroundColor = ConsoleColor.White;

			Console.Error.Write( "         /D" );

```
			Console.ResetColor( );
```

			Console.Error.Write( "         do not show " );

			Console.ForegroundColor = ConsoleColor.White;

```
			Console.Error.Write( "D" );
```
```
			Console.ResetColor( );
```

			Console.Error.WriteLine( "uplicate matches" );

```
 
```

			Console.ForegroundColor = ConsoleColor.White;

			Console.Error.Write( "         /F:nn" );

```
			Console.ResetColor( );
```

			Console.Error.Write( "      search only the " );

			Console.ForegroundColor = ConsoleColor.White;

```
			Console.Error.Write( "F" );
```
```
			Console.ResetColor( );
```
```
			Console.Error.Write( "irst " );
```

			Console.ForegroundColor = ConsoleColor.White;

```
			Console.Error.Write( "nn" );
```
```
			Console.ResetColor( );
```
```
			Console.Error.WriteLine( " bytes" );
```
```
 
```

			Console.ForegroundColor = ConsoleColor.White;

			Console.Error.Write( "         /G:nn" );

```
			Console.ResetColor( );
```

			Console.Error.Write( "      return match " );

			Console.ForegroundColor = ConsoleColor .White;

```
			Console.Error.Write( "G" );
```
```
			Console.ResetColor( );
```
```
			Console.Error.Write( "roup " );
```

			Console.ForegroundColor = ConsoleColor.White;

```
			Console.Error.WriteLine( "#nn" );
```
```
			Console.ResetColor( );
```
```
 
```

			Console.ForegroundColor = ConsoleColor.White;

			Console.Error.Write( "         /I" );

```
			Console.ResetColor( );
```

			Console.Error.Write( "         case " );

			Console.ForegroundColor = ConsoleColor.White;

```
			Console.Error.Write( "I" );
```
```
			Console.ResetColor( );
```

			Console.Error.WriteLine( "nsensitive search" );

```
 
```

			Console.ForegroundColor = ConsoleColor.White;

			Console.Error.Write( "         /L" );

```
			Console.ResetColor( );
```

			Console.Error.Write( "         single " );

			Console.ForegroundColor = ConsoleColor.White;

```
			Console.Error.Write( "L" );
```
```
			Console.ResetColor( );
```

			Console.Error.WriteLine( "ine mode: ^ and $ match begin and end of each line" );

```
 
```

			Console.ForegroundColor = ConsoleColor.White;

			Console.Error.Write( "         /Q         Q" );

```
			Console.ResetColor( );
```

			Console.Error.WriteLine( "uiet mode: no message if no match is found" );

```
 
```

			Console.ForegroundColor = ConsoleColor.White;

			Console.Error.Write( "         /S:nn      S" );

```
			Console.ResetColor( );
```

			Console.Error.Write( "kip the first " );

			Console.ForegroundColor = ConsoleColor.White;

```
			Console.Error.Write( "nn" );
```
```
			Console.ResetColor( );
```

			Console.Error.WriteLine( " matches" );

```
 
```

			Console.ForegroundColor = ConsoleColor.White;

			Console.Error.Write( "         /T:nn      T" );

```
			Console.ResetColor( );
```
```
			Console.Error.Write( "ake only " );
```

			Console.ForegroundColor = ConsoleColor.White;

```
			Console.Error.Write( "nn" );
```
```
			Console.ResetColor( );
```

			Console.Error.WriteLine( " matches" );

```
 
```
```
			Console.Error.WriteLine( );
```
```
 
```
```
			Console.Error.Write( "Example: " );
```

			Console.ForegroundColor = ConsoleColor.White;

			Console.Error.WriteLine( @"ROBOCOPY D:\sourcedir E:\targetdir /NP /MIR |" );

```
 
```

			Console.Error.WriteLine( @"         RXGREP ""\s+\d+\s+D:\\sourcedir\\[^\n\r]*\r\n([^\n\r\\]+\r\n)+""" );

```
			Console.ResetColor( );
```
```
 
```

			Console.Error.WriteLine( "         (to be read as a single command line) will return something like:" );

```
 
```

			Console.ForegroundColor = ConsoleColor.White;

			Console.Error.WriteLine( @"                         125    D:\sourcedir\subdir\" );

```
 
```

			Console.Error.WriteLine( "            New File                 342        brandnewfile.ext" );

```
 
```

			Console.Error.WriteLine( "            Newer                  4.06m        updatedfile.ext" );

```
 
```

			Console.Error.WriteLine( "          *EXTRA File              2.40m        deletedfile.ext" );

```
			Console.ResetColor( );
```
```
 
```
```
			Console.Error.WriteLine( );
```
```
 
```

			Console.Error.Write( "Notes:   If " );

			Console.ForegroundColor = ConsoleColor.White;

```
			Console.Error.Write( "/F:nn" );
```
```
			Console.ResetColor( );
```

			Console.Error.Write( " is used and a file is specified, only the first " );

			Console.ForegroundColor = ConsoleColor.White;

```
			Console.Error.Write( "nn" );
```
```
			Console.ResetColor( );
```
```
			Console.Error.WriteLine( " bytes" );
```
```
 
```

			Console.Error.WriteLine( "         of that file will be read; if the input is redirected, it is read" );

```
 
```

			Console.Error.Write( "         entirely, and then chopped to " );

			Console.ForegroundColor = ConsoleColor.White;

```
			Console.Error.Write( "nn" );
```
```
			Console.ResetColor( );
```

			Console.Error.WriteLine( " bytes before being searched." );

```
 
```
```
 
```

			Console.ForegroundColor = ConsoleColor.White;

			Console.Error.Write( "         /G:nn" );

```
			Console.ResetColor( );
```

			Console.Error.WriteLine( " can be used multiple times; all matching groups are written" );

```
 
```

			Console.Error.Write( "         to screen, separated by spaces, unless " );

			Console.ForegroundColor = ConsoleColor.White;

```
			Console.Error.Write( "/A" );
```
```
			Console.ResetColor( );
```

			Console.Error.WriteLine( " is used, in which case" );

```
 
```
```
 
```

			Console.Error.WriteLine( "         the matches will be separated by tabs; matching groups are shown" );

```
 
```

			Console.Error.WriteLine( "         in order of input, not in order of command line arguments, e.g." );

```
 
```

			Console.ForegroundColor = ConsoleColor.White;

			Console.Error.Write( "         /G:1 /G:3" );

```
			Console.ResetColor( );
```

			Console.Error.Write( " will show the same result as " );

			Console.ForegroundColor = ConsoleColor.White;

```
			Console.Error.Write( "/G:3 /G:1" );
```
```
			Console.ResetColor( );
```
```
			Console.Error.WriteLine( "." );
```
```
 
```

			Console.Error.Write( "         Switches " );

			Console.ForegroundColor = ConsoleColor.White;

```
			Console.Error.Write( "/D" );
```
```
			Console.ResetColor( );
```
```
			Console.Error.Write( " and " );
```

			Console.ForegroundColor = ConsoleColor.White;

```
			Console.Error.Write( "/G" );
```
```
			Console.ResetColor( );
```

			Console.Error.Write( " cannot be combined with " );

			Console.ForegroundColor = ConsoleColor.White;

```
			Console.Error.Write( "/S" );
```
```
			Console.ResetColor( );
```
```
			Console.Error.Write( " or " );
```

			Console.ForegroundColor = ConsoleColor.White;

```
			Console.Error.Write( "/T" );
```
```
			Console.ResetColor( );
```
```
			Console.Error.WriteLine( "." );
```
```
 
```

			Console.Error.WriteLine( "         Return code (\"errorlevel\") will equal the number of matches found," );

```
 
```

			Console.Error.WriteLine( "         or -1 in case of (command line) errors." );

```
 
```
```
			Console.Error.WriteLine( );
```
```
 
```

			Console.Error.WriteLine( "Written by Rob van der Woude" );

```
 
```

			Console.Error.WriteLine( "https://www.robvanderwoude.com" );

```
 
```
```
			#endregion Display Help Text
```
```
 
```
```
 
```
```
			return -1;
```
```
		}
```
```
 
```
```
		#endregion Error Handling
```
```
	}
```
```
}
```